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The effects of electromagnetic (EM) radiation have received increased attention, closely associated with the widespread use of electronics and wireless communication. A significant development in the area is the recent adoption of metal‐organic frameworks (MOFs) to effectively enable electromagnetic interference (EMI) shielding. MOF tunable molecular scaffold architecture offers numerous pathways to generate customizable magnetic and electrical properties, which are prerequisite materials characteristics for efficient EMI shielding performance. Their flexibility in terms of structural design, accompanied by high porosity and large specific surface area, makes MOFs excellent candidates to shield EM waves at multiple scales. Herein, the crucial role of molecular‐, nano‐, micro‐, and macro‐scale structural design is reviewed in accordance with the shielding performance of MOFs. The current design strategies of MOF‐based EMI shields are systematically outlined, and the shielding mechanisms are also expounded based on their structural features. The factors that hinder the widespread utilization of functional MOF‐derived EMI shields are also examined. Future research directions are unveiled for the rational design of the next‐generation MOF‐based EMI shields to address the pressing EM radiation concerns. [ABSTRACT FROM AUTHOR]

Ferroelectric materials hold significant potential for ultralow-energy-consuming oxide electronics and have recently been pointed out as a suitable platform for next-generation neuromorphic and reservoir computing schemes. We provide a brief overview of the progress in engineering electric dipole textures of epitaxial ferroelectric oxide thin films, with an emphasis on the technologically relevant ultrathin regime. In epitaxial films that are only a few unit-cells thick, surface chemistry and interfacial electrostatics are commonly considered limiting factors in ferroelectric device integration, as they may suppress the net ferroelectric behavior. Here, we highlight how nanoscale lattice chemistry control, including off-stoichiometry and layer polarization in oxides, can, in fact, emerge as powerful tools for engineering ferroelectricity in thin films. We also discuss the potential of such an approach in the context of recent trends in the field, such as the design of ferroelectric freestanding membranes and the optical control of polarization in thin films. Hence, with our Perspective article, we aim to provide key insights on the use of lattice chemistry for ferroelectricity engineering in thin films to facilitate exciting developments in ferroelectric-based applications. [ABSTRACT FROM AUTHOR]

Steelmaking contributes 8% to the total CO2 emissions globally, primarily due to coal-based iron ore reduction. Clean hydrogen-based ironmaking has variable performance because the dominant gas-solid reduction mechanism is set by the defects and pores inside the mm- to nm-sized oxide particles that change significantly as the reaction progresses. While these governing dynamics are essential to establish continuous flow of iron and its ores through reactors, the direct link between agglomeration and chemistry is still contested due to missing measurements. In this work, we directly measure the connection between chemistry and agglomeration in the smallest iron oxides relevant to magnetite ores. Using synthesized spherical 10-nm magnetite particles reacting in H2, we resolve the formation and consumption of wüstite (Fe1-xO)-the step most commonly attributed to whiskering. Using X-ray diffraction, we resolve crystallographic anisotropy in the rate of the initial reaction. Complementary imaging demonstrated how the particles self-assemble, subsequently react, and grow into elongated whisker structures. Our insights into how morphologically uniform iron oxide particles react and agglomerate in H2 reduction enable future size-dependent models to effectively describe the multiscale aspects of iron ore reduction.

[Display omitted] Manipulating the chirality at nanoscale has drawn great attention among scientists, considering its pivotal role in various applications of current interest, including nano-optics, biomedicine, and photocatalysis. In this work, we delve into this arena by fabricating chiral Swiss roll nanoarray (SRNA) continuous films employing colloidal lithography. The technique permits the dimension of Swiss roll metamaterials to reduce to nanoscale, thus achieving chiroptical response (circular dichroism (CD)) in the visible region. The interplay between the CD signals and plasmon resonance modes is revealed through theoretical simulations, enabling a deep understanding of chiral plasmonic metamaterials. The polarization-sensitive photocatalytic activity of chiral SRNAs is investigated, noting a marked increase in the reaction rate when the chirality of SRNAs matches with the handedness of circularly polarized light (CPL). Notably, the SRNA continuous films based on substrate possess integration and reusability without complex recycling process, enhancing their practicality in applications like sensing and plasmonic nanochemistry, particularly toward polarization-dependent photocatalysis. [ABSTRACT FROM AUTHOR]

Referring to selected examples of reproducible green syntheses using hybrid sol‐gel catalysts of the SiliaCat series from different doctoral theses and research works published between 2015 and early 2024, this study briefly illustrates how said catalysts have been applied in a number of green synthetic methods of significant industrial relevance. This shows evidence that the nanochemistry "bottom‐up" sol‐gel approach based on catalytic species entrapped in organically modified silicas as effective and versatile heterogeneous catalysts developed between the late 1990s and 2010 has succeeded. Subsequent developments will show how the use of said materials in automated syntheses, supplying data to machine learning algorithms actually leads to faster and cheaper optimization of the reaction conditions. Said progress ultimately will further accelerate industrial uptake of heterogeneous catalysis under flow in the fine chemical industry whose reluctance to change processes was due to the need to replace financially amortized (and expensive) production plants. [ABSTRACT FROM AUTHOR]

This article provides information on the integration of nanochemistry into secondary education curricula in Lower Saxony, Germany. It discusses the Nan_OS school laboratory setting, which aims to teach students about the properties, applications, opportunities, and risks of nanochemistry. The article also presents three innovative experiments that can be used in secondary education to introduce students to the synthesis and applications of nanoparticles. It emphasizes the importance of adapting school curricula to reflect current research and developments in nanotechnology and highlights the need for further development of experiments in the field of nanochemistry to support teachers in creating research-based lesson plans. [Extracted from the article]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa's first-ever master's in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program's framework, successes and challenges, related research, and future plans. [ABSTRACT FROM AUTHOR]

Advancements in nanochemistry have led to the development of engineered gold nanostructures (GNSs) with remarkable potential for a variety of dental healthcare applications. These innovative nanomaterials offer unique properties and functionalities that can significantly improve dental diagnostics, treatment, and overall oral healthcare applications. This review provides an overview of the latest advancements in the design, synthesis, and application of GNSs for dental healthcare applications. Engineered GNSs have emerged as versatile tools, demonstrating immense potential across different aspects of dentistry, including enhanced imaging and diagnosis, prevention, bioactive coatings, and targeted treatment of oral diseases. Key highlights encompass the precise control over GNSs' size, crystal structure, shape, and surface functionalization, enabling their integration into sensing, imaging diagnostics, drug delivery systems, and regenerative therapies. GNSs, with their exceptional biocompatibility and antimicrobial properties, have demonstrated efficacy in combating dental caries, periodontitis, peri-implantitis, and oral mucosal diseases. Additionally, they show great promise in the development of advanced sensing techniques for early diagnosis, such as nanobiosensor technology, while their role in targeted drug delivery, photothermal therapy, and immunomodulatory approaches has opened new avenues for oral cancer therapy. Challenges including long-term toxicity, biosafety, immune recognition, and personalized treatment are under rigorous investigation. As research at the intersection of nanotechnology and dentistry continues to thrive, this review highlights the transformative potential of engineered GNSs in revolutionizing dental healthcare, offering accurate, personalized, and minimally invasive solutions to address the oral health challenges of the modern era. [ABSTRACT FROM AUTHOR]

Colloidal metasurfaces are emerging as promising candidates for the development of functional chemical metamaterials, combining the undisputed control over crystallography and surface chemistry achieved by synthetic nanochemistry with the scalability and versatility of colloidal self‐assembly strategies. In light of recent reports of colloidal plasmonic materials displaying high‐performing optical cavities, this Minireview discusses the use of this type of metamaterials in the specific context of non‐linear optical phenomena and non‐linear molecular spectroscopies. Our attention is focused on the opportunities and advantages that colloidal nanoparticles and self‐assembled plasmonic metasurfaces can bring to the table compared to more traditional nanofabrication strategies. Specifically, we believe that future work in this direction will express the full potential of non‐linear molecular spectroscopies to explore the chemical space, with a deeper understanding of plasmon‐molecule dynamics, plasmon‐mediated processes, and surface‐enhanced chemistry. [ABSTRACT FROM AUTHOR]

In this research work, different chemical modifications were applied to gold nanoparticles and their use in enhanced non-classical light emitters based on metal-enhanced fluorescence (MEF) was evaluated. In order to achieve this, gold core–shell nanoparticles with silica shells were modified via multilayered addition and the incorporation of a covalently linked laser dye to develop MEF. Their inter-nanoparticle interactions were evaluated by using additional silica shell multilayers and modified cyclodextrin macrocycles. In this manner, the sizes and chemical surface interactions on the multilayered nanoarchitectures were varied. These optical active nanoplatforms led to the development of different nanoassembly sizes and luminescence behaviors. Therefore, the interactions and nanoassembly properties were evaluated by using various spectroscopic and nanoimaging techniques. Highly dispersible gold core–shell nanoparticles with diameters of 50–60 nm showed improved colloidal dispersion that led to single ultraluminescent gold core–shell nanoparticles with MEF. Then, the addition of variable silica lengths produced increased interactions and consequent nanoaggregation. However, the silanized nanoparticles were easily dispersible after agitation or sonication. Thus, their sizes were proportional only to the diameter and the van de Waals interaction did not affect their sizes in bulk. Then, the covalent linking of different concentrations of modified cyclodextrins was applied to the chemical surfaces by incorporating additional hydroxyl groups from the glucose monomeric unities of cyclodextrins. In this manner, variable larger-sized and inter-branched grafted gold core–shell silica nanoparticles were generated. The ultraluminescent properties were conserved due to the non-optical activity of the cyclodextrins. However, they generated enhanced ultraluminescence phenomena. Laser fluorescence microscopy nanoimaging showed enhanced resolutions in comparison to non-grafted supramolecular gold core–shell nanoparticles. The differences in their interactions and the sizes of the nanoassemblies were explained by their single nanoparticle diameters and the interacting chemical groups on their nanosurfaces. While the varied luminescence emissions generated were tuned by plasmonics, enhanced plasmonic phenomena and light scattering properties were seen depending on the type of nanoassembly. Thus, optically active and non-optically active materials led to different optical properties in the bright field and enhanced the excited state within the electromagnetic near-field of the gold nanotemplates. In this manner, it was possible to achieve high sensitivity by varying the spacer lengths and optical properties. Therefore, further perspectives regarding the design of nano-tools composed of light for various applications were discussed. [ABSTRACT FROM AUTHOR]

In this context, first-time cobalt chromite nanoparticles (CoCr2O4 NPs) were synthesized using honey as a natural precursor through a bio-derived approach. The benefits of this protocol are an easy workup using inexpensive precursors. The textural characteristics of the as-synthesized CoCr2O4 NPs were examined via XRD, FTIR, UV, FESEM, EDX mapping, and VSM studies. Microscopic pictures revealed a cuboidal topology with a mean size of 31.69 nm for greenly produced CoCr2O4 NPs. Furthermore, CoCr2O4 NPs were applied as a heterogeneous catalyst for the facile and one-step formation of 5-aryl-[1,2,4]-triazolidine-3-thiones. The proposed approach offers several admirable benefits, such as straightforwardness, benign reaction systems, shorter reaction time, facile workup, and excellent yield. Also, the as-prepared nanocatalyst was reused (up to 5 cycles) without reducing the significant catalytic performance. Therefore, the present study discloses that synthesizing CoCr2O4 NPs by a facile green approach and assessing robust catalytic performance might benefit nanochemistry research, offering new avenues for organic transformations. [ABSTRACT FROM AUTHOR]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa’s first-ever master’s in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program’s framework, successes and challenges, related research, and future plans.

This review covers major aspects of nanochemistry in Ukraine. It describes current state of the field, lists main contributors and discuss the trends and limitations of its development. Ukraine's nanotechnology can be traced back to the country's rich scientific heritage, which includes a long tradition of excellence in materials science, chemistry, and physics. Despite limited and sporadic financial support, nanochemistry has occupied decent plase in the country scientific agenda. Related courses in the education institution contributed to the formation of the generation of skilled chemists who build their successful career internationally. [ABSTRACT FROM AUTHOR]

Defect and interface engineering, which can facilitate exceptional electrochemical stability and activity, are some of the most important strategies in devising electrode materials. However, the complex nanoscale chemistry and structure characteristics make the origin of electrochemical mechanism extremely difficult to understand. To eliminate this issue, the delicately designed 1D tungsten bronze superstructure anode, guided by defect and interface engineering, is successfully prepared for sodium storage to gain insight into the endogenous structure‐property relationships. It can realize the intensely enhanced Na+‐storage performance with a safe operating potential of ≈0.5 V, a high specific capacity of 228 mAh g−1 at 0.1 C and superior rate performance, which is attributed to the rapid electron and ion transfer process induced by abundant heterointerfaces. More importantly, it can convey an ultra‐stable long‐term cycling performance, with the capacity retention close to 90% after 4500 cycles at 5 C and 10000 cycles at 10 C, which can be explained by the inherently zero‐strain characteristic of a novel vacancy‐ordered superstructure in tungsten bronze Ba3.4Nb10O28.4 (BNO). This study reveals the structural origins of defect and interface engineering responsible for electrochemical mechanism, providing critical insight into the design of superior electrode materials. [ABSTRACT FROM AUTHOR]

Molecular electronics break-junction experiments are widely used to investigate fundamental physics and chemistry at the nanoscale. Reproducibility in these experiments relies on measuring conductance on thousands of freshly formed molecular junctions, yielding a broad histogram of conductance events. Experiments typically focus on the most probable conductance, while the information content of the conductance histogram has remained unclear. Here we develop a microscopic theory for the conductance histogram by merging the theory of force-spectroscopy with molecular conductance. The procedure yields analytical equations that accurately fit the conductance histogram of a wide range of molecular junctions and augments the information content that can be extracted from them. Our formulation captures contributions to the conductance dispersion due to conductance changes during the mechanical elongation inherent to the experiments. In turn, the histogram shape is determined by the non-equilibrium stochastic features of junction rupture and formation. The microscopic parameters in the theory capture the junction's electromechanical properties and can be isolated from separate conductance and rupture force (or junction-lifetime) measurements. The predicted behavior can be used to test the range of validity of the theory, understand the conductance histograms, design molecular junction experiments with enhanced resolution and molecular devices with more reproducible conductance properties. Conductance histograms are common setups to study molecular junctions, but the dispersion of the signals makes it difficult to interpret at microscopic level. Here the authors develop a physical model of molecular junctions that connects this observable with molecular properties. [ABSTRACT FROM AUTHOR]

Steelmaking contributes 8% to the total CO2 emissions globally, primarily due to coal-based iron ore reduction. Clean hydrogen-based ironmaking has variable performance because the dominant gas–solid reduction mechanism is set by the defects and pores inside the mm- to nm-sized oxide particles that change significantly as the reaction progresses. While these governing dynamics are essential to establish continuous flow of iron and its ores through reactors, the direct link between agglomeration and chemistry is still contested due to missing measurements. In this work, we directly measure the connection between chemistry and agglomeration in the smallest iron oxides relevant to magnetite ores. Using synthesized spherical 10-nm magnetite particles reacting in H2, we resolve the formation and consumption of wüstite (Fe1-xO)—the step most commonly attributed to whiskering. Using X-ray diffraction, we resolve crystallographic anisotropy in the rate of the initial reaction. Complementary imaging demonstrated how the particles self-assemble, subsequently react, and grow into elongated “whisker” structures. Our insights into how morphologically uniform iron oxide particles react and agglomerate in H2 reduction enable future size-dependent models to effectively describe the multiscale aspects of iron ore reduction. [ABSTRACT FROM AUTHOR]

The essential importance of the psychological and professional training of the young generation and the adaptation of society to the tasks and problems of the use of nanotechnology is shown. It was noted that an important way to modernize education is the introduction of a system of specialized training in secondary schools, which involves taking into account the educational needs, inclinations and abilities of students, creating conditions for professional self-determination. Ways of differentiating education are shown. The importance and necessity of improving the qualifications of teachers of general education natural sciences as a necessary step for the introduction of elective courses was noted. Examples of topics related to the methodical training of teachers in the fields of nanophysics, nanochemistry, and nanobiology are given. The content and methodological ideas of the elective course «Modern Nanochemistry» are presented. The purpose, tasks and requirements for the mastery level of this course are highlighted. The results of the course should be the acquisition of knowledge on the basics of nanotechnology and nanochemistry, the main principles and achievements of nanochemistry, methods of its research, unique properties of nanomaterials, their application and prospects for the development of nanochemistry, the role of nanochemistry in solving common human problems. Appropriate criteria are proposed for evaluating the implementation of the course program. Students are expected to conduct scientific research, prepare essays and multimedia presentations. The proposed elective course consists of invariant and variable parts. The approximate content of the course includes seven most important topics. It is envisaged that students will carry out project activities as a method of increasing interest and holistic study of school subjects. Resource support for the course «Modern nanotechnological chemistry» was recommended, which includes recommended educational and methodological literature, Internet resources, and national periodicals on nanotechnology. [ABSTRACT FROM AUTHOR]

A significant paradigm shift has been observed in the past decade in the area of theranostics owing to the development of various isotropic and anisotropic metal nanostructures, simultaneous with improved imaging modalities. Platinum-based nanostructures are advancing in a plethora of clinical applications as theranostics tools owing to their unique behavior concerning their size, shape, and surface chemistry at the nanoscale regime. Platinum nanostructures are optically active and provide significant potential to the field of theranostics by simplifying diagnosis and therapeutics, thus providing key solutions through nano-enabled technologies. The review emphasizes the potential of platinum nanostructures that have immense potential in vitro and in vivo scenarios as nanocarriers. Still, their potential in terms of photothermal active agents has not been well explored or reported. Nanotheranostics has emerged as a platform where various noble metal nanoparticles are effectively efficient as photothermal agents in bringing precision to therapy and diagnostics. Platinum, as an antioxidant and a stable nanocarrier, will enable them to act as photosensitizers when conjugated to affinity molecules and plays a key role in efficient treatment and diagnosis. The review envisions bringing together the possibilities of the safe-by-design synthesis of platinum nanostructures and their potential role in both in vitro and in vivo applications. A roadmap describing the challenges, pitfalls, and possibilities of influencing platinum nanostructures to overcome the existing biological/targeting barriers is elaborated. This review provides a literature survey on platinum nanostructures in theranostics, providing novel strategies in bio-imaging, diagnostics, and nanomedicine. [ABSTRACT FROM AUTHOR]

Nanoparticle studies are groundbreaking today, largely due to unpredictable changes in particle size and surface properties. Therefore, nanoparticles are considered as building blocks in optoelectronics, pharmaceuticals, nuclear energy, bioengineering, biomedicine and industrial applications. Today, the importance of environmentally friendly methods is increasing. The use of the green synthesis method, which adopts an economic synthesis approach that will reduce resource and energy consumption and do not harm the environment, is also encouraged in every field. In the study, biosafe ascorbic acid was used as an alternative reagent (agent) to the chemical reduction method. The method process performed with the reagent selected for nanoparticle synthesis has ensured that it is green synthesis, which is adopted as non-toxic and environmentally friendly. In this study, nanoparticles were synthesized by reducing the sulphate, nitrate, chloride and acetate salts of Cu(II), Ni(II), Co(II), Zn(II) and Mn(II) transition metals with the reducing agent ascorbic acid compound. It is aimed to investigate the effects of the same metal cations and different anion salts on nanoparticle synthesis. Depending on the radius ratios and solubility values of metal cations and anions, the nanoparticle obtained from Ni(CH3COO)2 salt has the smallest radius. Nano metal particles with the largest radius were obtained as a result of reduction from Co(NO3)2 salt. The characterization of the synthesized nanoparticles were recorded by particle size analysis and scanning electron microscopy (SEM) images. [ABSTRACT FROM AUTHOR]

The ability to image cell chemistry at the nanoscale is key for understanding cell biology, but many optical microscopies are restricted by the ~(200–250)nm diffraction limit. Electron microscopy and super-resolution fluorescence techniques beat this limit, but rely on staining and specialised labelling to generate image contrast. It is challenging, therefore, to obtain information about the functional chemistry of intracellular components. Here we demonstrate a technique for intracellular label-free chemical mapping with nanoscale (~30 nm) resolution. We use a probe-based optical microscope illuminated with a mid-infrared laser whose wavelengths excite vibrational modes of functional groups occurring within biological molecules. As a demonstration, we chemically map intracellular structures in human multiple myeloma cells and compare the morphologies with electron micrographs of the same cell line. We also demonstrate label-free mapping at wavelengths chosen to target the chemical signatures of proteins and nucleic acids, in a way that can be used to identify biochemical markers in the study of disease and pharmacology. Intracellular structures are mapped in human multiple myeloma cells through label-free chemical mapping at nanoscale resolution, yielding sub-diffraction images of the ER, mitochondria and nucleoli. [ABSTRACT FROM AUTHOR]

The layered allotropes of group 15 (P, As, Sb and Bi), also called two-dimensional (2D) pnictogens, have emerged as one of the most promising families of post-graphene 2D-materials. This is mainly due to the great variety of properties they exhibit, including layer-dependent bandgap, high charge-carrier mobility and current on/off ratios, strong spin–orbit coupling, wide allotropic diversity and pronounced chemical reactivity. These are key ingredients for exciting applications in (opto)electronics, heterogeneous catalysis, nanomedicine or energy storage and conversion, to name a few. However, there are still many challenges to overcome in order to fully understand their properties and bring them to real applications. As a matter of fact, due to their strong interlayer interactions, the mechanical exfoliation (top-down) of heavy pnictogens (Sb & Bi) is unsatisfactory, requiring the development of new methodologies for the isolation of single layers and the scalable production of high-quality flakes. Moreover, due to their pronounced chemical reactivity, it is necessary to develop passivation strategies, thus preventing environmental degradation, as in the case of bP, or controlling surface oxidation, with the corresponding modification of the interfacial and electronic properties. In this Feature Article we will discuss, among others, the most important contributions carried out in our group, including new liquid phase exfoliation (LPE) processes, bottom-up colloidal approaches, the preparation of intercalation compounds, innovative non-covalent and covalent functionalization protocols or novel concepts for potential applications in catalysis, electronics, photonics, biomedicine or energy storage and conversion. The past years have seen the birth of the chemistry of pnictogens at the nanoscale, and this review intends to highlight the importance of the chemical approach in the successful development of routes to synthesise, passivate, modify, or process these materials, paving the way for their use in applications of great societal impact. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation (SDIE) is emerging as a promising pathway to solving the worldwide water shortage and water pollution. Nanomaterials (e.g., plasmonic metals, inorganic/organic semiconductors, and carbon nanomaterials) and related nanochemistry have attracted increasing attention for the solar-to-vapor process in terms of broadband absorption, electronic structure adjustment, and surface/interface chemistry manipulation. Furthermore, the assembly of nanomaterials can contribute to the mass transfer, heat management, and enthalpy regulation of water during solar evaporation. To date, numerous nano-enabled materials and structures have been developed to improve the solar absorption, heat management (i.e., heat confinement and heat transfer), and water management (i.e., activation, evaporation, and replenishment). In this review, we focus on a systematical summary about the composition and structure engineering of nanomaterials in SDIE, including size and morphology effects, nanostructure optimizations, and structure-property relationship decoupling. This review also surveys recent advances in nanochemistry (e.g., preparation chemistry and structural chemistry) deployed to conceptual design of nanomaterials. Finally, the key challenges and future perspectives of nanomaterials for solar evaporation are overviewed. This review aims at providing guidance for the design and construction of nanomaterials for high-efficiency SDIE on the basis of the aspects of materials science and chemical engineering. [ABSTRACT FROM AUTHOR]

In this research work, different chemical modifications were applied to gold nanoparticles and their use in enhanced non-classical light emitters based on metal-enhanced fluorescence (MEF) was evaluated. In order to achieve this, gold core–shell nanoparticles with silica shells were modified via multilayered addition and the incorporation of a covalently linked laser dye to develop MEF. Their inter-nanoparticle interactions were evaluated by using additional silica shell multilayers and modified cyclodextrin macrocycles. In this manner, the sizes and chemical surface interactions on the multilayered nanoarchitectures were varied. These optical active nanoplatforms led to the development of different nanoassembly sizes and luminescence behaviors. Therefore, the interactions and nanoassembly properties were evaluated by using various spectroscopic and nanoimaging techniques. Highly dispersible gold core–shell nanoparticles with diameters of 50–60 nm showed improved colloidal dispersion that led to single ultraluminescent gold core–shell nanoparticles with MEF. Then, the addition of variable silica lengths produced increased interactions and consequent nanoaggregation. However, the silanized nanoparticles were easily dispersible after agitation or sonication. Thus, their sizes were proportional only to the diameter and the van de Waals interaction did not affect their sizes in bulk. Then, the covalent linking of different concentrations of modified cyclodextrins was applied to the chemical surfaces by incorporating additional hydroxyl groups from the glucose monomeric unities of cyclodextrins. In this manner, variable larger-sized and inter-branched grafted gold core–shell silica nanoparticles were generated. The ultraluminescent properties were conserved due to the non-optical activity of the cyclodextrins. However, they generated enhanced ultraluminescence phenomena. Laser fluorescence microscopy nanoimaging showed enhanced resolutions in comparison to non-grafted supramolecular gold core–shell nanoparticles. The differences in their interactions and the sizes of the nanoassemblies were explained by their single nanoparticle diameters and the interacting chemical groups on their nanosurfaces. While the varied luminescence emissions generated were tuned by plasmonics, enhanced plasmonic phenomena and light scattering properties were seen depending on the type of nanoassembly. Thus, optically active and non-optically active materials led to different optical properties in the bright field and enhanced the excited state within the electromagnetic near-field of the gold nanotemplates. In this manner, it was possible to achieve high sensitivity by varying the spacer lengths and optical properties. Therefore, further perspectives regarding the design of nano-tools composed of light for various applications were discussed.

Artificial photosynthesis is an attractive approach for the generation of renewable fuels because such systems will be suitable for deployment on highly abundant, non-arable land. Recently emerged methods of nanoscience to create conformal, ultrathin oxide layers enable the hierarchical integration of light absorbers, catalysts, and membranes into systems with far simpler synthetic approaches than available till now. This holds in particular for the coupling of molecular light absorbers and catalysts for sunlight to fuel conversion, providing photoelectrodes with greatly improved stability. Moreover, the use of ultrathin inert oxides as proton conducting, molecule impermeable membranes has opened up the integration of reduction and oxidation half reactions into complete photosynthetic systems on the shortest possible length scale—the nanometer scale. This capability affords minimization of energy-degrading resistance losses caused by ion transport over macroscale distances while separating the incompatible water oxidation and carbon dioxide reduction catalysis environments on the nanoscale. Understanding of charge transport between molecular components embedded in the oxide layers is critical for guiding synthetic design improvements of the light absorber-catalyst units to optimize performance and integrate them into complete artificial photosystems. Recent results and insights from transient optical, vibrational, and photoelectrochemical studies are presented, and future challenges and opportunities for engaging dynamic spectroscopies to accelerate the development of nanoscale integrated artificial photosystems are discussed. [ABSTRACT FROM AUTHOR]

This contribution underlines the key role of physicochemical characterisation techniques in the area of medical research. The starting point centres on the Mid-InfraRed platform located at the Tenon hospital and dedicated to multidisciplinary functional investigations. In the last two decades, we have enhanced this platform by creating a network combining researchers from varied disciplines such as physicists, chemists, and clinicians. The resultant research dynamism is underscored by metrics such as 71 references in Pubmed and 129 in Web of Science, and the high impact of the journals in which we have published (New England Journal of Medicine, Kidney International, Chemical Review...). It is of paramount importance to disseminate these physicochemical techniques among young doctors, and to establish collaborations with appropriate private companies.

Single‐particle tracking and optical tweezers are powerful techniques for studying diverse processes at the microscopic scale. The stochastic behavior of a microscopic particle contains information about its interaction with surrounding molecules, and an optical tweezer can further facilitate this observation with its ability to constrain the particle to an area of interest. Although these techniques found their initial applications in biology, they can also shed new light on microscopic interface phenomena by unveiling nanoscale morphologies and molecular‐level interactions in real time, which are obscured in traditional ensemble analysis. Here, the application of single‐particle tracking and optical tweezers are demonstrated for studying molecular interactions at solid–liquid interfaces. Specifically, the surfactant behaviors at the water–glass interface are investigated by tracing gold nanoparticles that are optically trapped on these molecules. The underlying mechanisms governing the particle motion, which can be explained by hydrophobic interactions, disruptions, and rearrangements among surfactant monomers at the interfaces, are discovered. These interpretations are further supported by statistical analysis of an individual trajectory and comparison with theoretical predictions. The findings provide new insights into the surfactant dynamics and also illustrate the promise of single‐particle tracking and optical manipulation for studying nanoscale physics and chemistry of surfaces and interfaces. [ABSTRACT FROM AUTHOR]

This communication aims at discussing strategies based on developments from nanotechnology focused on the next generation of sequencing (NGS). In this regard, it should be noted that even in the advanced current situation of many techniques and methods accompanied with developments of technology, there are still existing challenges and needs focused on real samples and low concentrations of genomic materials. The approaches discussed/described adopt spectroscopical techniques and new optical setups. PCR bases are introduced to understand the role of non-covalent interactions by discussing about Nobel prizes related to genomic material detection. The review also discusses colorimetric methods, polymeric transducers, fluorescence detection methods, enhanced plasmonic techniques such as metal-enhanced fluorescence (MEF), semiconductors, and developments in metamaterials. In addition, nano-optics, challenges linked to signal transductions, and how the limitations reported in each technique could be overcome are considered in real samples. Accordingly, this study shows developments where optical active nanoplatforms generate signal detection and transduction with enhanced performances and, in many cases, enhanced signaling from single double-stranded deoxyribonucleic acid (DNA) interactions. Future perspectives on miniaturized instrumentation, chips, and devices aimed at detecting genomic material are analyzed. However, the main concept in this report derives from gained insights into nanochemistry and nano-optics. Such concepts could be incorporated into other higher-sized substrates and experimental and optical setups. [ABSTRACT FROM AUTHOR]

[Display omitted] • A one-step method for high-yield paper-based self-synthesis of gold nanoparticles. • Nano-gold is formed without the use of any externally added reducing agent. • Opto-active and catalytic applicability of paper-supported nano-gold is illustrated. The paper (a typical nanoparticle support scaffold) is generally considered to be chemically inert and their inherent capabilities to self-generate nanoparticles have been largely overlooked. Here we present our experimental findings on the use of simple paper as a versatile green nanochemical reactor. We find that gold nanoparticles can be massively formed in paper in the absence of any externally added reducing agent or applied charge. Employing only an aqueous chloroauric solution under rather mild pH condition on paper at room temperature, this method is capable of efficiently fabricating supported nanoparticles. The flexible application of the paper-supported nanoparticles in opto-functional or catalytic frameworks is also illustrated. [ABSTRACT FROM AUTHOR]